This invention relates to an assembling tool and more particularly to a tool which draws the ends of sections of duct together and holds them for permanent assembly.
Ducts are used in many applications to convey substances. One well known application is the use of ducts in air conditioning to transport air which has been heated or cooled. Such ducts as those used in air conditioning are generally rectangular in cross section and manufactured from sheet metal stock. Other shaped cross sections such as oval or circular are readily available and are used in other applications. Ducts are also made of various materials such as plastic, concrete and procelain to name a few.
Often ducting is used to convey substances over some distance. In many applications it is impractical or impossible to construct a continuous duct which has no seams or joints. For this reason ducting is generally manufactured in sections which are usually fitted either at the place of manufacture or at the place of assembly with various type flanges for permanently joining the sections. For example, the type of duct typically used in air conditioning applications has at least two of the sides of the rectangular cross section rolled over, curved or bent away from the opening toward the outside of the duct. This forms a type of flange which allows two adjoining ducts to be secured at the flanges by sheet metal screws or a clamp placed over two such flanges to hold the two adjoining ducts securely. Other types of ducts are supplied or fitted with a collar at the end of each duct section. This collar forms the flange. When two duct sections are to be fastened, bolts may be placed through holes in the flanges of each duct section after aligning and tightened to securely fasten them together.
Certain problems are presently encountered when installing and assembling the ducts or duct sections on the application site. The duct sections often needed for a particular application often come in sizes which are cumbersome and hard to maneuver, yet at the same time the ducts must be joined in an exacting fashion to prevent any leakage. In addition to size, the length, duct wall thickness and the material from which it is manufactured determines the weight of the duct section, and if substantial this weight can also create certain installation problems.
Presently the method of assembling two sections requires that they be placed in relatively close proximity to each other. Then by use of conventional tools such as hammers and manual labor, the sections may be forced or hammered into place by striking the flange thus pushing one section toward the other. This striking or forcing continues until the sections are aligned and in contact with each other. Then an appropriate fastener is applied to make a permanent assembly of the sections. The use of a hammer or other excessive force on a malleable material such as sheet metal may cause the flange and duct to become distorted thus preventing a proper seal between the sections. This then necessitates an on-site repair which causes waste in additional labor and material. Often the duct will be extensively damaged to the degree that an entire section must be replaced. In the case of concrete or porcelain ducts, the use of a hammer or other excessive force on such brittle material often causes them to break or shatter. This renders the duct section totally worthless and useless, and requires the replacement of the duct which again results in lost labor time and material.
Another problem encountered in the installation and assembling of duct sections by conventional methods is improper alignment. Generally when two sections are placed in proximate relation to each other for assembling, it is difficult to align them so that a fluid tight joint is made. Usually one of the sections must be moved or shifted by hammering, lifting or otherwise forcing it into proper alignment. Therefore, when aligning with conventional methods, damages similar to those above may be encountered.
A still further problem often encountered is that after two sections of duct are properly aligned and set, they will often shift or otherwise become misaligned if no axial force or pressure is maintained on the duct sections until a proper fastener is applied to the duct flanges. Often times because of duct placement or other difficulties it is hard to maintain sufficient axial pressure or force to insure proper alignment until a fastener is applied. This can cause a faulty or leaky joint which requires additional labor, time and materials to repair.